Field
The disclosed technology generally relates to apparatuses for reducing or cancelling noise generated by a tire in motion, and more particularly to a noise-reducing apparatus including a sound-absorbing foam and a fixing structure for attaching and fixing the sound-absorbing foam to a tire. The disclosed technology also relates to a tire having the noise-reducing apparatus and a method of integrating the noise-reducing apparatus to a tire.
Description of the Related Technology
Noise can be generated by a tire in motion due to air being repeatedly compressed and expanded in the tire, which is in turn due to vibrations being generated by the tread of the tire being repeatedly compressed and restored. The noise generated by such process is sometimes called the resonance noise. The resonance noise can travel into the interior of a vehicle and heard by the driver and/or passenger(s) as sounds having sharp peaks, thereby degrading the riding experience and comfort. Tire resonance noise has been considered as a severe problem due to a low aspect ratio and inch-up of tires.
Accordingly, studies on the low-noise tire having an acoustic absorbent materials have been recently been conducted. Low-noise tires are generally manufactured by machining an acoustic absorbent material and placing it in the cavity of a tire or attaching it to the rim or the inner liner.
In this respect, a low noise tire composed of a sealant layer attached to the inner side of an inner liner and an acoustic absorbent layer including a polypropylene melt blow fiber and a polymer fiber at a predetermined ratio on the sealant layer has been disclosed in Korean Patent No. 10-1535029 (hereafter, referred to as ‘Prior Art 1’). Further, a technology of reducing tire resonance noise in a tire by putting a spherical acoustic absorbent of 40 to 100 mm in a tire without fixing the absorbent has been disclosed in Japanese Patent Application Publication No. 2002-240507 (hereafter, referred to as ‘Prior Art 2’). The spherical acoustic absorbent is inserted in a tire cavity, but is not bonded to prevent heat generation. However, adhesive ability has been improved by materials having high resistance against high-temperature heat and improvement of adhesive ability and it is difficult to apply a spherical acoustic absorbent due to reduction of the tire cavity, as the aspect ratio of tires has been recently decreased. Further, when a tire is rotated without the acoustic absorbent fixed, the spherical shape may be deformed or unbalance may be caused.